The initial announcement of Google Compute Engine last year limited access to a small number of specifically invited developers, but Google has now widened access to the preview to anyone who wants to try the service.

The announcement was made alongside details of a data storage service and the addition of PHP support in Google App Engine, which until now only supported Java, Python, and Google Go.

Google is still playing catch-up with the big names in cloud infrastructure, particularly Amazon Web Services. It began its push with the release of App Engine as a platform-as-a-service (PaaS) for hosting web apps. Compute Engine competes with Amazon Elastic Compute Cloud (EC2), and like EC2 gives you the means to run your apps on Google’s infrastructure.

In a blog post about the development, Navneet Joneja said that Google is announcing several new capabilities that make it easier and more economical to use Compute Engine for a broader set of applications.

One improvement to Compute Engine is support for sub-hour billing. Joneja said:

“We heard feedback from our early users who wanted more granular billing increments so they could run short-lived workloads. Now all instances are charged for in one-minute increments with a ten-minute minimum, so you don’t pay for compute minutes that you don’t use.”

Another improvement for smaller apps is the addition of new shared-core instance types. There are two new types, micro and small instance, designed as a cost-effective option for running small workloads that don’t need a lot of CPU power, like development and test workloads.

Going the other way, you can now have much larger persistent disks, with the ability to attach up to 10 terabytes of persistent disk to a Compute Engine virtual machine. Software-defined routing has also been added, and you can configure instances to function as gateways, configuring VPN servers and building applications that span your local network and Google’s cloud.